<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgl - multiple renderers</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
        <!-- <link type="text/css" rel="stylesheet" href="main.css"> -->
        <script src="../src/three.js"></script>
		<style>
			body {
				background-color: #fff;
				color: #444;
			}
			a {
				color: #08f;
			}
		</style>
	</head>
	<body>
		<script>
			// import * as THREE from '../build/three.module.js';
			var camera, scene, renderer1, renderer2;
			var mesh1, mesh2, mesh3;
			var color = new THREE.Color();
			init();
			animate();
			function init() {
				camera = new THREE.PerspectiveCamera( 20, window.innerWidth / ( window.innerHeight / 2 ), 1, 10000 );
				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0xffffff );
				var light = new THREE.DirectionalLight( 0xffffff );
				light.position.set( 0, 0, 1 );
				scene.add( light );
				var light = new THREE.DirectionalLight( 0xffff00, 0.75 );
				light.position.set( 0, 0, - 1 );
				scene.add( light );
				// shadow
				var canvas = document.createElement( 'canvas' );
				canvas.width = 128;
				canvas.height = 128;
				var context = canvas.getContext( '2d' );
				var gradient = context.createRadialGradient( canvas.width / 2, canvas.height / 2, 0, canvas.width / 2, canvas.height / 2, canvas.width / 2 );
				gradient.addColorStop( 0.1, 'rgba(210,210,210,1)' );
				gradient.addColorStop( 1, 'rgba(255,255,255,1)' );
				context.fillStyle = gradient;
				context.fillRect( 0, 0, canvas.width, canvas.height );
				var shadowTexture = new THREE.CanvasTexture( canvas );
                // shadow
				var shadowMaterial = new THREE.MeshBasicMaterial( { map: shadowTexture } );
				var shadowGeo = new THREE.PlaneBufferGeometry( 300, 300, 1, 1 );
				var shadowMesh;
                
				shadowMesh = new THREE.Mesh( shadowGeo, shadowMaterial );
				shadowMesh.position.y = - 250;
				shadowMesh.rotation.x = - Math.PI / 2;
				scene.add( shadowMesh );
				shadowMesh = new THREE.Mesh( shadowGeo, shadowMaterial );
				shadowMesh.position.x = - 400;
				shadowMesh.position.y = - 250;
				shadowMesh.rotation.x = - Math.PI / 2;
				scene.add( shadowMesh );
				shadowMesh = new THREE.Mesh( shadowGeo, shadowMaterial );
				shadowMesh.position.x = 400;
				shadowMesh.position.y = - 250;
				shadowMesh.rotation.x = - Math.PI / 2;
				scene.add( shadowMesh );
				var radius = 200;
				var geometry1 = new THREE.IcosahedronBufferGeometry( radius, 1 );
				var count = geometry1.attributes.position.count;
				geometry1.addAttribute( 'color', new THREE.BufferAttribute( new Float32Array( count * 3 ), 3 ) );
				var geometry2 = geometry1.clone();
				var geometry3 = geometry1.clone();
				var positions1 = geometry1.attributes.position;
				var positions2 = geometry2.attributes.position;
				var positions3 = geometry3.attributes.position;
				var colors1 = geometry1.attributes.color;
				var colors2 = geometry2.attributes.color;
				var colors3 = geometry3.attributes.color;
				for ( var i = 0; i < count; i ++ ) {
					color.setHSL( ( positions1.getY( i ) / radius + 1 ) / 2, 1.0, 0.5 );
					colors1.setXYZ( i, color.r, color.g, color.b );
					color.setHSL( 0, ( positions2.getY( i ) / radius + 1 ) / 2, 0.5 );
					colors2.setXYZ( i, color.r, color.g, color.b );
					color.setRGB( 1, 0.8 - ( positions3.getY( i ) / radius + 1 ) / 2, 0 );
					colors3.setXYZ( i, color.r, color.g, color.b );
				}
				var material = new THREE.MeshPhongMaterial( {
					color: 0xffffff,
					flatShading: true,
					vertexColors: THREE.VertexColors,
					shininess: 0
				} );
				var wireframeMaterial = new THREE.MeshBasicMaterial( { color: 0x000000, wireframe: true, transparent: true } );
				mesh1 = new THREE.Mesh( geometry1, material );
				mesh1.position.x = - 400;
				mesh1.rotation.x = - 1.87;
				scene.add( mesh1 );
				var wireframe = new THREE.Mesh( geometry1, wireframeMaterial );
				mesh1.add( wireframe );
				mesh2 = new THREE.Mesh( geometry2, material );
				mesh2.position.x = 400;
				scene.add( mesh2 );
				var wireframe = new THREE.Mesh( geometry2, wireframeMaterial );
				mesh2.add( wireframe );
				mesh3 = new THREE.Mesh( geometry3, material );
				scene.add( mesh3 );
				var wireframe = new THREE.Mesh( geometry3, wireframeMaterial );
				mesh3.add( wireframe );
				//
				renderer1 = new THREE.WebGLRenderer( { antialias: true } );
				renderer1.setPixelRatio( window.devicePixelRatio );
				renderer1.setSize( window.innerWidth, window.innerHeight / 2 );
				document.body.appendChild( renderer1.domElement );
				renderer2 = new THREE.WebGLRenderer();
				renderer2.setPixelRatio( window.devicePixelRatio );
				renderer2.setSize( window.innerWidth, window.innerHeight / 2 );
				document.body.appendChild( renderer2.domElement );
			}
			function animate() {
				requestAnimationFrame( animate );
				// update scene
				mesh1.rotation.z += Math.PI / 500;
				mesh2.rotation.z += Math.PI / 500;
				mesh3.rotation.z += Math.PI / 500;
				var position = new THREE.Vector3();
				var color = new THREE.Color();
				var time = performance.now() / 500;
				var positions = mesh3.geometry.attributes.position;
				var colors = mesh3.geometry.attributes.color;
				for ( var i = 0, l = positions.count; i < l; i ++ ) {
					position.fromArray( positions.array, i * 3 );
					color.setRGB( 1, Math.sin( time + position.x ), Math.cos( time * 2.123 + position.x ) );
					colors.setXYZ( i, color.r, color.g, color.b );
				}
				colors.needsUpdate = true;
				//
				var time = performance.now() / 2000;
				camera.position.x = Math.sin( time ) * 1800;
				camera.position.z = Math.cos( time ) * 1800;
				camera.lookAt( scene.position );
				renderer1.render( scene, camera );
				renderer2.render( scene, camera );
			}
		</script>

	</body>
</html>